Magnetically operated clamshell bucket



"Dec. 29, 1936.

F. w. JEssoP MAGNETICALLY OPERATED CLAMSHELL BUCKET Filed Jan. 12, 1935 Zinnentor (Ittornegs Patented Dec. 29, 1936 UNITED STATES PATENT OFFICE MAGNETIC'ALLY OPERATED CLAMS HELL BUCKET Application January 12, 1935, Serial No. 1,452

13 Claims.

My invention relates to improvements in devices for handling materials and more particularly relates to an improved magnetically operated multi-part bucket for use with cranes.

Electro-magnets, although very effective in the handling of bulky magnetic materials, are quite useless in handling non-magnetic material and are not efficient in handling finely divided magnetic materials such as borings. Heretofore it has been common practice in magnet equipped cranes and hoists, when non-magnetic materials and the like were to be handled, to remove the magnet and substitute a multi-part bucket such as a clamshell or orange peel bucket. Aside from the possibility that the crane might not be properly equipped to handle the ordinary multi-part bucket was the fact that it took considerable time to make the change-over.

Some attempts have been made to construct attachments that could be used with a magnet but these devices were cumbersome, taking nearly as much time to attach as it did to make the before described change-over, and after installation were not efficient nor effective except in a very limited manner.

By the devices embodying my invention I am able to overcome the disadvantages present in the prior art. One of the devices constructed according to my invention is disclosed in the accompanying specification and drawing.

In the drawing:

Fig. 1 is a side elevational view of a magnet with a multi-part bucket of the clamshell type;

Fig. 2 is an end elevational view of the magnet and bucket of Fig. 1;

Fig. 3 is like Fig. 1 but showing the scoops in an open position; and

Fig. 4 is a View on areduced scale taken on line 4-4 of Fig. 1 looking in the direction of the arrows.

Briefly stated I contemplate combining an electro-magnet with a multi-part bucket whereby I am able to utilize the magnetic forces set up upon energization of the electro-magnet to close the bucket.

In the drawing I have illustrated one embodiment of my invention wherein one of my devices is shown as attached to a circular magnet of the concentric or annular bi-polar type. It is to be understood that the application of my invention is not to be limited to attachment to any particular type of magnet. Modifications in the structure of the attachment will also be apparent to those skilled in the art and it is not my intention to limit the invention to the specific structure disclosed.

The electro-magnet illustrated may be of the bi-polar type comprising a large circular housing 1 suspended by chains and a ring 2. The chains are connected to ears 4 on the top 5 of the housing. The magnet hasan interior winding adapted to be electrically energized through a cable, not shown. The poles of the magnet may consist of an inner center pole and a concentric outer pole, this being one of the most common type. The lower portion of the housing flares outwardly at the lower end.

A supporting frame IU of generally annular formation is provided and is recessed as indicated at l l to permit the flared end of the magnet to extend into the recess. At spaced points about the periphery of the frame upwardly extended bosses [2 are provided and studs l3 extend inwardly and downwardly through threaded apertures and engage the magnet housing. When tightened, the studs draw the frame into close engagement with the outer pole of the magnet furnishing a close magnetic coupling therewith. This type of frame and the manner of attaching it to the magnet may obviously be varied widely. For example it may also be effectively replaced by a ring consisting of two or more parts bolted together about the circumference of the magnet, or by a one-piece ring member of sufiicient size to slip over the top of the magnet but small enough to prevent it from passing over the bottom portion, or the frame may be held to the magnet by straps extending over the top thereof.

The scoops of the buckets are supported below the magnet by two pairs of links I 5 which are pivotally secured at l6 on opposite sides of the frame. The ends of the links are pivotally connected at l! to the extremities [8 of the bucket halves or scoops 19. The other ends of the links project upwardly beyond the pivot Hi to form arms 20, adapted to engage at a predetermined point with the abutment 40 to limit the opening of the bucket. The side walls of the scoops are provided with upwardly projecting extensions 23 which form the leaves of hinges 24 connecting the scoops to each other.

A pair of armatures, adapted to be moved by energization of the magnet and in turn to close the bucket, are disposed beneath the magnet, being hingedly connected by pins 3| to bosses 30 at diametrically opposite points on the frame l0. Each armature has a large fiat body 32 from which extends a pair of parallel arms 34, the extremities being journalled on the pins 3| on op posite sides of the boss 30. Each armature has a semi-circular thickened portion 33 adapted to be attracted by the magnet field to the center pole of the magnet. Lateral arms 35 extend from opposite sides of the armatures and are pivotally connected by links 38 to the bucket scoops at points 31 spaced from the connecting links I5. Means to assure that the armatures move together toward the magnet is provided and comprises a downwardly extending off-set portion 3! at the extremity of each armature, which, as best shown in Figs. 3 and 4, is adapted to engage with the bottom of the opposite armature and overlap the same, to form an interlocking engagement therebetween.

Intermediate the levers 20, the bosses l2 are widened to provide abutments 40 which serve as stop members for limiting the movement of the levers 20, preventing the bucket hinge from opening past or to dead center as well as preventing swinging of the scoops when in an open position. It will be understood that certain of the parts which make up the device such as the armatures 33 and frame, l0 should be made of magnetic material.

The operation of the device is as follows:

The device assembled as shown in Fig. 1 and the magnet being de-energized, when it is raised from the ground through the usual cables and pulleys connected to the link 2, the gravitational pull upon the scoops of the bucket and upon the armatures causes the scoops of the bucket to open to the positions best illustrated in Fig. 3. As previously stated the amount of opening of the bucket is limited, so that the hinge connection 24 of the scoops cannotgo to or past dead center and thus prevent reclosing of the bucket.

The device is lowered onto and allowed to rest on the pile of material to be moved. The magnet is now energized electrically in the usual manner.. Energization of the magnet attracts the armatures 33 toward the center pole where they may contact completing the magnetic circuit from the center pole through the armature and the body 32 to the frame and outer pole. The

" frame and the body of the armatures being magnetically permeable, furnish an eificient path for the magnetic flux. Attraction of the armatures to the center pole necessarily rotates each armature on its hinge,v and since each armature has an off-set portion 31 extending beneath the other armature, neither is capable of contacting or approaching the center pole first or ahead of the other. Should one armature show an inclination to travel upward ahead of the other, the portion 31 engages the underside of the opposite armature and forces it upwardly therewith. Upward movement of the armature is communicated through the links 36 to the scoops l9, pulling the scoops toward each other until they reach the position shown in Fig. l, where the edges 50 of the scoops abut and the bucket is closed.

A slight gap may be providedbetween the armatures and the center pole of the magnet to prevent any residual magnetism remaining in the armatures from .holding the armatures against the center pole and retaining the scoops in closed position after de-energization of the magnet.

By providing a structure as shown with the armatures thus linked to the scoops of the bucket, a minimum amountof air gap is maintained between the armatures and the center magnet pole with a maximum opening of the bucket, maintaining the armatures well-within the magnetic field of the energizing magnet and assuring positive operation upon energization of the magnet.

It is quite obvious that the substantially square type of bucket shown could be changed for clamshell buckets having other conformation or to still other types such as an orange peel bucket. Still other numerous and extensive departures may be made from the invention as disclosed, but without departing from the spirit of the invention or the scope of the appended claims.

I claim:

1. A device of the class described comprising in combination an electro-magnet, a multi-scoop bucket, armature means hinged to the magnet and connected to the bucket and movable relative to the bucket for bringing together the scoops of the bucket when the magnet is energized.

2. In a device of the class described comprising an electro-magnet, a supporting frame operatively associated with the magnet, a multiscoop bucket pivotally suspended from the frame below the magnet and means connected to the bucket and frame and movable relative to the magnet, said means being operable upon energization of the magnet to close the bucket.

3. In a magnetically operated clamshell bucket, an electro-magnet, a supporting frame carried by the magnet, a pair of links pivotally carried by said frame, a pair of scoops pivoted to said links below the magnet, and means including a pair of armatures, means connecting the armatures to the frame and scoops and movable relative to said magnet, said means being operable upon electrical energization of the magnet to bring the scoops together.

4. In a device of the class described, an electromagnet, a bucket supporting frame connected to the magnet, a pair of links pivotally carried on said frame, a pair of scoops pivoted to said links below the magnet, means including a pair of armatures pivotally supported by said frame and connected to the scoops and movable relative to the magnet, upon electrical energization of the magnet, to bring the scoops together.

5. In a device of the class described, an electro-magnet, a supporting frame adapted to be connected to the magnet, links pivotally carried by said frame, a pair of clamshell scoops pivoted to said links below the magnet and hinged together, armatures hingedly supported by the frame below the magnet, links connecting the armatures to the scoops, said armatures being adapted upon energization of the magnet to travel toward the magnet and bring the scoops together.

6. A clamshell bucket attachment for an electro-magnet comprising a frame operatively associated with a magnet, links pivotally carried by said frame and a multi-scoop bucket suspended below the magnet on said links, armatures hingedly supported by the frame below and adjacent the magnet, links connecting the armatures to the scoops, said armatures adapted upon energization of the magnet to travel toward the magnet and move the scoops of the bucket to a closed position, a tongue upon each of said armatures adapted to cooperate with the other armature to cause the scoops to move toward each other simultaneously.

7. In a device of the class described, an electro-magnet, a frame supported from the magnet, a multi-scoop bucket having the scoops connected to each other, supporting links pivotally connected to said frame at points spaced from their ends and to the scoops of the bucket at the other ends,

and means operable upon electrical energization of the magnet to move the scoops to a closed position comprising armatures hingedly secured to said frame and links connecting said armatures to said scoops, tongues carried by each of the armatures and adapted to extend below each opposing armature to cause the armatures to move toward the magnet simultaneously and stop means adapted to be engaged by the free end of the scoop supporting links to limit the amount of opening of the bucket.

8. A clamshell bucket for attachment to and operation by an electro-magnet including a bucket supporting member adapted to be secured to the magnet, scoop supporting links pivotally connected to said member at points spaced from their ends, a pair of clamshell scoops carried by said links and hingedly connected together, means operable upon electrical energization of the magnet to move the scoops to a closed position comprising a pair of armatures hingedly secured to opposite points on said member and adapted to extend below the magnet, links connecting said armatures to said scoops, tongues carried by each armature and adapted to extend below each opposing armature to cause the armatures to move simultaneously, abutments carried by said frame and adapted to be engaged by the ends of the scoop supporting links to limit the pivotal movement of said links and limit the amount of opening of the bucket.

9. In a device in the class described in combination with an electro-magnet having inner and outer poles, a bucket supporting frame secured to the magnet and magnetically coupled to the outer pole of the magnet, a pair of links pivotally carried on said frame, and a multi-part bucket pivoted to the links, and means operable upon electrical energization of the magnet to move the scoops to a closed position, comprising a pair of armatures pivotally secured toand magnetically coupled to said frame and connected to the bucket and adapted to complete the magnetic coupling between the frame and the center pole of the magnet.

10. In a device of the class described, in combination with an electro-magnet, a bucket supporting frame connected to said magnet and forming a path for a magnetic field, a multi-part bucket including a pair of scoops hingedly connected to each other, links pivotally mounted on said frame and connected to said scoops, the ends of said links extending beyond the pivot on said frame and forming levers; abutments carried by the frame and adapted for engagement with said levers to limit the amount of pivotal movement of said links and the opening of the bucket; means operable upon energization of the magnet to draw the scoops to a closed position comprising armatures hingedly and magnetically coupled to said frame adapted to complete the path for the magnetic field of the magnet and adapted to be moved toward the magnet upon energization thereof, said armatures being interlocked so that when one moves toward the center pole of the magnet, the other is moved simultaneously therewith and links connecting said armatures to said scoops at points spaced from the supporting links.

11. In a device of the class described a magnet including a base, a multi-part bucket pivotally supported thereby, armature means disposed en-- tirely outside of the magnet and pivotally connected to the bucket and magnet, said armature means being movable toward the magnet and relative to the bucket to close the bucket due to energization of the magnet.

12. In a device of the class described, an electro-magnet, a supporting frame adapted to be connected to the magnet, a pair of scoops pivotally connected to said magnet and hinged together, armatures hingedly supported by the frame below the magnet, links connecting the armatures to the scoops, said armatures being adapted upon energization of the magnet to travel toward the magnet and bring the scoops together, tongues carried by each armature and adapted to extend below each opposing armature to cause the armatures to move simultaneously.

13. In a device of the class described, in combination with an electro-magnet, a bucket supporting frame connected to said magnet and forming a path for a magnetic field, a multi-part bucket including a pair of scoops hingedly connected to each other and pivotally connected to the magnet, means operable upon energization of the magnet to draw the scoops to a closed position comprising armatures hingedly and magnetically coupled to said frame adapted to complete the path for the magnetic field of the magnet and adapted to be moved toward the magnet upon energization thereof, said armatures being interlocked so that when one moves toward the center pole of the magnet, the other is moved simultaneously therewith and links connecting said armatures to said scoops at points spaced from the pivotal connection to the magnet.

FRANCIS WOODWARD JESSOP. 

